TV's 5 Best 'What If?'Episodes

The Walking Dead pulled out all the stops for Danai Gurira's last (for awhile, at least) appearance as Michonne. As well as her discovery that Rick Grimes may still be alive, the episode features a hallucination sequence showing us how Michonne's life would have turned out differently had she not saved Andrea at the end of Season Two.

Alternate reality or 'What If?' episodes are a staple of Television. While some exist for humour's sake, others are interesting explorations of 'the road not taken'.

Here are some of TV's best 'What If? episodes.

1. 'If/Then' (Grey's Anatomy, Season 8, Ep.13)

In the eighth season of long running medical drama Grey's Anatomy, leading lady Meredith Grey finds herself imagining what life would have been like if her Mother, world-renowned surgeon Ellis Grey, had never been diagnosed with Alzheimer's. What results is a world very different from the one we know.

Meredith, on the surface, is a lot happier. Her Mother, the Chief Of Surgery in this universe, is married to Richard Webber, giving Meredith the Father-figure she never had in the original timeline. Meredith is engaged to Alex Karev, leaving Derek Shepherd trapped in an unhappy marriage to Addison. In a world where she never connected with Meredith, Lexie Grey is a troubled drug addict. Perhaps the most jarring change is that Meredith and Cristina, usually inseparable, are not friends at all.. at least to begin with. As the shine dulls on the 'shiny-happy' alternate universe, the episode's final message is that even if the path we take getting there is different, some things are simply meant to be.

"What if?...What..if? Your life is a gift. Accept it. No matter how screwed up or painful it seems to be. Some things are going to work out as if they were destined to happen. As if they were just meant to be."

2. Anthology Of Interest I & II (Futurama)

The two 'Anthology Of Interest' episodes, seen in Seasons two and three of Futurama, have the Planet Express crew using Professor Farnsworth's What If? machine to view alternate realities. The first episode answers questions such as 'What if Leela was more impulsive?' and 'What if Fry had never been frozen?', while the second, among other things, reveals what would happen if Bender became human.

Like many animated 'What ifs?' the Anthology Of Interest episodes aren't meant to be taken seriously. However, if you enjoy Futurama's usual humour, they're good for a laugh.

3. 'Lexmas' (Smallville, Season 5, ep. 9)

When Lex Luthor is shot in an alleyway, he experiences a Christmas Carol-like coma dream in which he is transported to a potential idyllic future, guided by the ghost of his Mother, Lillian. While his Father has disowned him, Lex has everything else he desires: He is married to Lana Lang, with an adorable son, and another baby on the way. Lillian tells Lex that this perfect life could be his, if he makes the right choices- ie, dropping out of the Senatorial race in favour of Jonathan Kent.

Lex, deeply in love with Lana at the time, is almost sold on the idea. Unfortunately, things go horribly wrong when the alternate Lana dies in childbirth. Lex immediately rejects the timeline, not wanting to lose someone else he loves. It is this choice that makes Lex's journey down the slippery slope to villainy truly unstoppable.

4. 'The One That Could Have Been' (Friends, Season 6, ep. 15 & 16)

After learning her ex, Barry, is getting a divorce, Rachel finds herself wondering what would have happened if she had gone through with marrying him at the beginning of the series, leading to a chain reaction in which the Friends imagine their own 'What If?' scenarios. The imagining leads to a world where Monica is still overweight, Ross is trapped in a loveless marriage to Susan, Phoebe is an overworked stockbroker, and Joey still stars on Days Of Our lives, with Chandler as his new assistant.

Like the earlier Grey's example, the two-part episode ends with the implication that no matter how different things may seem, some things are just meant to be.

5. 'The Wish' (Buffy The Vampire Slayer, Season 3, ep. 9)

Left heartbroken and embarrassed after her break up with Xander, Cordelia wishes that Buffy Summers never came to Sunnydale, but immediately regrets her decision when the wish is granted by a demon. Without Buffy around to stop the Harvest at the beginning of the first season, the town is overrun by vampires, including, sadly, Xander and Willow. To make things worse, The Master was never killed.

The episode provides a twist, in that while you'd usually expect the person who made the wish to ultimately save the day, Cordelia is killed off early on. The hero is Giles, working entirely on faith that the other world is better.

'The Wish' is considered one of the best episodes of Buffy, and provides a great set up for the equally loved 'Doppelgangland' later in season three.

Whether just for fun or a clever exploration of character, 'What If?' episodes can be the best in a series, and as they are usually stand alone, are easy to revisit. Now might be a good time to rewatch your own favourite 'What If?' episodes.