"Avengers: Infinity War" is highly anticipated by fans of the Marvel Cinematic Universe (MCU) because it is set to tie up all the movies in the series together. The film will revolve around Thanos, a powerful supervillain, and his quest to gain the Infinity Stones, powerful objects that can potentially destroy worlds. Observant MCU fans have since taken note of where these can be currently found.

Cheat Sheet just released a list of where the known Infinity Stones are, based on what was shown in the films. The first is the Space Stone, otherwise known as the Tesseract. This appeared in "Captain America," but had a more prominent impact in "The Avengers" when it was used by Loki to open a portal to Chitauri, allowing the aliens to wreak havoc in New York. The stone was then placed in Odin's vault in Asgard, which means that the stone can once again surface in "Thor: Ragnarok" during Hela's invasion.

The Mind Stone was first seen in "The Avengers," embedded in Loki's scepter. Hydra then managed to get its hands on this on "Avengers: Age of Ultron," using the stone's power to power up the twins Scarlet Witch and Quicksilver. Ultron attempted to use the stone to inhabit a body, only to have this backfire on him when Tony Stark's artificial intelligence Jarvis came to life instead as Vision.

The Reality Stone, or Aether. appeared in "Thor: The Dark World." Dr. Jane Foster accidentally assimilated it in her body, leading to her being kidnapped by Malekith. He was thwarted, and the Stone was stored in the Collector's Vault in Knowhere.

The Power Stone is the contested object in "Guardians of the Galaxy." Star-Lord was able to use the stone to defeat Ronan and save Xandar. The team then turned it over to the Nova Corps.

The Time Stone was featured in "Doctor Strange" as the Eye of Agamotto. Embedded in an amulet, this is under the custody of the sorcerers.

The only Infinity Stone that has not made an appearance is the Soul Stone, but given the MCU film lineup until 2018, it is likely that it will be seen before "Avengers: Infinity War."

"Avengers: Infinity War" is scheduled for release on May 4, 2018.