The upcoming episode of the hit action-crime TV series 'Arrow' is set to be big as The CW show will have a crossover with three other shows. Curious as to what happened in last week's episode? Read on and find out. Episode eight for the show's fifth season is titled "Invasion!", and the synopsis, via Spoiler TV, reads: ARROW CELEBRATES 100 EPISODES; THE EPIC SUPERHERO CROSSOVER CONTINUES - Oliver (Stephen Amell) wakes up to a life where he never got on The Queen's Gambit. Robert (guest star Jamey Sheridan) and Moira Queen (guest star Susanna Thompson) are alive and well.

Laurel (guest star Katie Cassidy) is his loving fiance and their wedding is imminent. Everything seems perfect, but Oliver starts to notice small imperfections that make him question this new reality. Meanwhile, Felicity (Emily Bett Rickards) and the recruits take on a new threat with help from The Flash (guest star Grant Gustin) and Supergirl (guest star Melissa Benoist).

Everything will be new for the fans of the hit show. The life Oliver could have lived if only he didn't board his father's yacht, The Queen's Gambit, and ended up getting stranded in Lian Yu island, is going to be shown this week. As shown in the promotional photos, his parents are still alive and he is getting married to Laurel.

But all these will be questionable even to Oliver. According to an article by Christian Times, Oliver notices things that will make him realize something is wrong. He will soon discover that he is stuck in a fabricated reality. However, this place where he is stuck might also be the reason he can finally move on from the past and heal his wounds.

Exciting, right? Tune in to The CW this Tuesday, November 29 for the full episode of "Invasion!" At 8 p.m. EST.